Answer:
C. Characters with little genetic variation will constrain the rate of natural selection
Explanation:
Natural selection can have an effect only as long as there are variations on characters on which it can select upon. Genetic variation is independent of the environment or the needs that a species may have to become better adapted to its changing environment. In other words, genetic mutations are the raw material on which natural selection can work. If there is a low rate for mutations to occur, then natural selection will proceed at a slow pace. The opposite is also true. Since mutation rate may be more frequent at some locations in a gene than at others, it can be predicted that the characters coded in that gene location will be more likely to be affected by natural selection and therefore what phenotype may be molded by natural selection.
Answer:
The correct answer is - C. retention of their own genome.
Explanation:
The endosymbiotic theory is a theory that suggests that eukaryotic cells are developed from prokaryotic cells. According to this theory, organelles like mitochondria are developed in eukaryotic cells as the result of proteo-bacteria cells engulfing aerobic bacteria.
The evidence of this theory can be seen as the mitochondria has their own genome such as circular DNA and ribosomes as the prokaryotes.
Answer and Explanation:
A gene is a section of DNA. The change in the sequence of the DNA is known as mutation. Mutation always changes the sequence of the DNA. Sunlight can cause mutation. Sunlight produces structures named thymine dimers. Thymine dimers produce twist in the shape of DNA. These twists make DNA hard to copy, which can lead to mutation. It is essential to use sunscreen to block UVA and UVB rays to prevent thymine dimers from emerging in our cells. The US Food and Drug Agency recommends an SPF (sun protection factor) to defend against skin aging and skin cancer. X-ray radiation is a form used in x-rays. The energy level of the X-ray radiation is very high that can produce free radicals. Free radicals can steal electrons from DNA that can cause mutation. By using medical images, we can decrease exposure to X-rays. Less exposure to X-rays prevents mutation and also prevents the production of gene protein in other body parts.
